Fabry disease, an X-linked systemic vasculopathy, is caused by a deficiency of α-galactosidase A resulting in globotriaosylceramide (Gb 3 ) storage in cells. The pathogenic role of Gb 3 in the disease is not known. Based on previous work, we tested the hypothesis that accumulation of Gb 3 in the vascular endothelium of Fabry disease is associated with increased production of reactive oxygen species (ROS) and increased expression of cell adhesion molecules. Gb 3 loading resulted in increased intracellular ROS production in cultured vascular endothelial cells in a dose-dependent manner. Increased Gb 3 also induced expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and E-selectin. Reduction of endogenous Gb 3 by treatment of the cells with an inhibitor of glycosphingolipid synthase or α-galactosidase A led to decreased expression of adhesion molecules. Plasma from Fabry patients significantly increased ROS generation in endothelial cells when compared with plasma from non-Fabry controls. This effect was not influenced by reduction of intracellular Gb 3 . This study provided direct evidence that excess intracellular Gb 3 induces oxidative stress and up-regulates the expression of cellular adhesion molecules in vascular endothelial cells. In addition, other factors in patient's plasma may also contribute to oxidative stress in Fabry vascular endothelial cells.

The use of stem cells has enabled the successful generation of simple organs. However, anatomically complicated organs such as the kidney have proven more refractory to stem-cell-based regenerative techniques. Given the limits of allogenic organ transplantation, an ultimate therapeutic solution is to establish self-organs from autologous stem cells and transplant them as syngrafts back into donor patients. To this end, we have striven to establish an in vitro organ factory to build up complex organ structures from autologous adult stem cells by using the kidney as a target organ. Cultivation of human mesenchymal stem cells in growing rodent embryos enables their differentiation within a spatially and temporally appropriate developmental milieu, facilitating the first step of nephrogenesis. We show that a combination of whole-embryo culture, followed by organ culture, encourages exogenous human mesenchymal stem cells to differentiate and contribute to functional complex structures of the new kidney.organogenesis ͉ regeneration